Such detectors, which are principally used in installations or machinery in which it is necessary to know the position of a movable metal article or piece, may be fixed on a support having, relative to the movement of that article, one of, for example, five particular orientations, one corresponding to the frontal orientation of the sensitive face and the others to the various lateral orientations of the sensitive face. The provision of such detectors is thus advantageous for the manufacturer, who can make his production operation cost-effective in this way, and for the user in so far as he need only have available a single stock of replacement detectors.
Proximity detectors are already known, for from DE-U-73 44 278 or FR-A-2 608 755, which comprise a housing, a mounting which can be positioned on the housing in a selected one of a plurality of orientations about an axis, and a detector head which can be associated with the mounting in a selected one of two orientations. In one of these two orientations, the sensitive face is frontal so that the direction of detection is parallel to said axis. In the other of the two abovementioned orientations, the sensitive face is lateral, so that the direction of detection is, relative to the axis, a radial direction determined by the orientation of the mounting about the axis. The detector head has the shape of a cube with a recess for receiving the mounting.
According to these documents, the detector head is fixed to the mounting by screws. However, the screw fixings occupy space in the head, especially since the threads need to be relatively long in order to be strong. This thread length increases the fitting time. Moreover, if the thread is damaged, fitting is no longer possible.
A detector is also known from FR-A-2 611 264 whose two-part mounting can lock the head in the various orientations envisaged There are no longer any screws between head and mounting, but on the other hand the two mounting parts are screwed one to the other.